Kevin Crutt commited on
Commit ·
ce80562
1
Parent(s): f8ee7f1
Apply rustfmt attack-verify fix
Browse files- src/lib.rs +316 -82
src/lib.rs
CHANGED
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@@ -34,29 +34,60 @@ pub enum Held {
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}
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fn blocks(d: &[u8]) -> Vec<u128> {
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d.chunks(BLOCK)
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}
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fn mod_inv(a: u128, m: u128) -> Option<u128> {
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fn e(a: i128, b: i128) -> (i128, i128, i128) {
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let (g, x, _) = e((a % m) as i128, m as i128);
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if g != 1 {
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Some((((x % m as i128) + m as i128) % m as i128) as u128)
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}
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/// The K shadow projections of a slice: residues of each block on each cylinder (the tomographic
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/// projections at K "angles"). Each shadow alone is lossy; enough of them reconstruct the slice.
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pub fn project_shadows(slice: &[u8]) -> Vec<Vec<u64>> {
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CYLINDERS
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}
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/// Reconstruct the exact slice from a SUBSET of shadows (the inverse Radon / CRT). `Held` if the
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/// subset's joint modulus doesn't cover a block (under-sampled angles -> ill-posed).
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pub fn reconstruct(
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let range = 1u128 << (8 * BLOCK as u32);
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let nb = shadows[subset[0]].len();
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let mut out = Vec::with_capacity(nb * BLOCK);
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@@ -69,10 +100,16 @@ pub fn reconstruct(shadows: &[Vec<u64>], subset: &[usize], orig_len: usize) -> R
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let diff = (((s as i128 - r as i128) % p as i128) + p as i128) % p as i128;
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r += m * ((diff as u128 * inv) % p);
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m *= p;
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if m >= range {
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}
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if m < range { return Err(Held::InsufficientShadows); }
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for i in (0..BLOCK).rev() { out.push(((r >> (8 * i as u32)) & 0xFF) as u8); }
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}
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out.truncate(orig_len);
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Ok(out)
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@@ -81,13 +118,23 @@ pub fn reconstruct(shadows: &[Vec<u64>], subset: &[usize], orig_len: usize) -> R
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// ---------------------------------------------------------------- metatagged deterministic sim
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/// A metatagged particle on the bounded torus grid.
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#[derive(Debug, Clone, PartialEq, Eq)]
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pub struct Particle {
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/// The simulated-universe STATE = a bounded grid of metatagged particles. Its serialization is the
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/// "slice"; the transition rule is constant-velocity torus drift (deterministic + REVERSIBLE, so
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/// retrodiction and extrapolation are the same operation at +/-t).
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#[derive(Debug, Clone, PartialEq, Eq)]
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pub struct SimState {
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impl SimState {
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/// Canonical serialization (particles sorted by tag) -> the slice bytes.
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@@ -108,15 +155,21 @@ impl SimState {
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out
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}
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pub fn deserialize(bytes: &[u8]) -> Option<SimState> {
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if bytes.len() < 6 {
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let w = u16::from_be_bytes([bytes[0], bytes[1]]);
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let h = u16::from_be_bytes([bytes[2], bytes[3]]);
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let n = u16::from_be_bytes([bytes[4], bytes[5]]) as usize;
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if w == 0 || h == 0 {
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let mut particles = Vec::with_capacity(n);
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for i in 0..n {
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let o = 6 + i * 12;
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if o + 12 > bytes.len() {
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particles.push(Particle {
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x: u16::from_be_bytes([bytes[o], bytes[o + 1]]),
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y: u16::from_be_bytes([bytes[o + 2], bytes[o + 3]]),
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@@ -129,34 +182,76 @@ impl SimState {
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}
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/// Deterministic, reversible transition by `dt` steps (constant-velocity torus drift).
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pub fn at(&self, dt: i64) -> SimState {
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let particles = self
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/// An IRREVERSIBLE step (the arrow of time): a particle that would leave the grid is CLAMPED to
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/// the edge and its velocity ZEROED - the pre-collision velocity is LOST. Once this happens,
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/// reverse-propagation cannot uniquely recover the past (many pasts map to this present).
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pub fn clamp_step(&self) -> SimState {
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let particles = self
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}
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}
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// ---------------------------------------------------------------- MTP movement matrix (the "time-travel" lens)
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fn torus_delta(from: u16, to: u16, m: u16) -> i32 {
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let (d, m) = (to as i32 - from as i32, m as i32);
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if d > m / 2 {
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}
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/// The total movement matrix the MTP-1/2/3 supervisors measure between two slices: per metatag,
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/// MTP1 = pixel delta (dx,dy), MTP2 = frequency/shell (speed), MTP3 = cylinder/residue (tag identity).
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@@ -174,8 +269,14 @@ impl MtpMovementMatrix {
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for pa in &a.particles {
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match b.particles.iter().find(|pb| pb.tag == pa.tag) {
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Some(pb) => {
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if pb.vx != pa.vx || pb.vy != pa.vy {
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}
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None => reversible = false,
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}
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@@ -183,20 +284,39 @@ impl MtpMovementMatrix {
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MtpMovementMatrix { moves, reversible }
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}
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fn apply(&self, state: &SimState, dir: i32) -> SimState {
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let particles = state
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}
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/// Reverse LeWorld through the lens: project the slice one tick into the PAST (retrodiction).
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pub fn project_reverse(&self, state: &SimState) -> SimState {
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/// Forward LeWorld: project the slice one tick into the FUTURE.
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pub fn project_forward(&self, state: &SimState) -> SimState {
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pub fn hbp(&self) -> String {
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format!("MTPMATRIX|moves={}|mtp1=pixel_delta|mtp2=frequency_shell|mtp3=cylinder_residue|reversible={}|lens=reverse_leworld_projection|body_in_row=0|json=0",
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self.moves.len(), self.reversible)
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@@ -235,7 +355,11 @@ impl SliceTimeReport {
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/// The deterministic regime (steps 1-6): reconstruct t0 from shadows (multi-cylinder / Q-PRISM),
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/// extrapolate the KNOWN rule forward and backward, and compare each predicted slice byte-for-byte
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/// against generated truth. Exact in the determined regime; `Held` if shadows are insufficient.
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pub fn run_deterministic(
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let slice0 = truth0.serialize();
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let shadows = project_shadows(&slice0);
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let recon = reconstruct(&shadows, subset, slice0.len())?;
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forward_exact.push((k, state0.at(k).serialize() == truth0.at(k).serialize()));
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backward_exact.push((-k, state0.at(-k).serialize() == truth0.at(-k).serialize()));
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}
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Ok(SliceTimeReport {
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}
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/// The HONEST BOUNDARY (step 6): given a truth slice that GAINED entropy the rule cannot fix (an
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/// injected particle, an external input), the deterministic prediction from `state0` will NOT match.
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/// Returns Err(PredictionDivergedNewEntropy) - the break is DETECTED, never silently "predicted".
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pub fn verify_or_detect_entropy(
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if state0.at(dt).serialize() == observed_future.serialize() {
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Ok(()) // determined: 0-loss
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} else {
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@@ -271,20 +403,36 @@ pub fn verify_or_detect_entropy(state0: &SimState, observed_future: &SimState, d
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// - no claim this IS the universe engine.
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#[derive(Debug, Clone, PartialEq, Eq)]
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pub enum Verdict {
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#[derive(Debug, Clone, Copy, PartialEq, Eq)]
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pub enum HeldReason {
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/// The watcher gate: reconstruct from `sufficient`; then every `cross` cylinder must agree with the
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/// reconstruction (catches a corrupted / hallucinated shadow). All agree -> verified classical clone.
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pub fn watcher_gate(
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let recon = match reconstruct(shadows, sufficient, orig_len) {
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Ok(r) => r,
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Err(_) => return Verdict::Held(HeldReason::InsufficientShadows),
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};
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for &ci in cross {
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let recomputed: Vec<u64> = blocks(&recon)
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}
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Verdict::VerifiedClone(recon)
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}
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/// FNV-1a 64-bit fold -> an 8-byte addressing digest (NOT a crypto hash).
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fn digest8(slice: &[u8]) -> [u8; 8] {
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let mut h = 0xcbf29ce484222325u64;
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for &b in slice {
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h.to_be_bytes()
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}
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fn hex8(b: &[u8; 8]) -> String {
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/// The OMNIBIT PIXEL - one pixel carrying the representation STACK as SELECTORS + CHECKS, not raw
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/// payload: position/tick/frequency, an 8-byte fold digest, the residual selector bits, the signed
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/// checks against the shared atlas. Not a magical all-information bit.
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#[derive(Debug, Clone, PartialEq, Eq)]
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pub struct OmnibitPixel {
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pub x: u16,
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pub digest8: [u8; 8],
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pub residual_bits: u8,
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pub capacity_margin_bits: i32,
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pub watcher_bound: u8,
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}
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impl OmnibitPixel {
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pub fn of(
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let roof = (n_cylinders.min(CYLINDERS.len()) as f64) * 25.0; // ~log2(2^25) per cylinder
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let block_bits = (8 * BLOCK) as f64;
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OmnibitPixel {
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x,
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residual_bits: (block_bits - roof).max(0.0).ceil() as u8,
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capacity_margin_bits: (roof - block_bits) as i32,
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watcher_bound,
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fn sample_state() -> SimState {
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SimState {
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w: 64,
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particles: vec![
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Particle {
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],
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}
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}
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fn serialize_roundtrips() {
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let s = sample_state();
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assert_eq!(SimState::deserialize(&s.serialize()).unwrap(), {
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let mut c = s.clone();
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});
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}
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fn rule_is_reversible() {
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let s = sample_state();
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for k in 1..=20 {
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assert_eq!(
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}
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}
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// enough shadows (all 4 cylinders) -> full state reconstructed -> every slice exact both ways
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let report = run_deterministic(&s, 25, &[0, 1, 2, 3]).unwrap();
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assert!(report.reconstructed_ok);
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assert!(
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assert_eq!(report.forward_exact.len(), 25);
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assert_eq!(report.backward_exact.len(), 25);
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}
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fn two_shadows_already_suffice_one_holds() {
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let s = sample_state();
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assert!(run_deterministic(&s, 5, &[0, 1]).unwrap().all_exact()); // 2 cylinders cover a 48-bit block
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assert!(matches!(
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}
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#[test]
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assert!(verify_or_detect_entropy(&s, &s.at(7), 7).is_ok());
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// but a future that GAINED entropy (an injected particle) is DETECTED, never manufactured:
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let mut injected = s.at(7);
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injected.particles.push(Particle {
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}
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#[test]
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let slice = b"the yin-yang watcher: black-absorb, white-emit, round-trip or Held";
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let shadows = project_shadows(slice);
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// clean: reconstruct from [0,1], cross-check [2,3] -> verified classical clone
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assert_eq!(
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// tamper a sufficient shadow -> the cross cylinders catch the hallucination -> Held
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let mut tampered = shadows.clone();
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tampered[0][0] = tampered[0][0].wrapping_add(1);
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assert_eq!(
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// too few -> Held (Shannon)
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assert_eq!(
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}
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#[test]
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assert!(px2.capacity_margin_bits >= 0); // over-determination margin, never negative storage
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let px1 = OmnibitPixel::of(slice, 3, 5, 7, 440, 1, 0);
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assert!(px1.residual_bits > 0); // 1 cylinder under-covers -> residual selector remains
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assert!(
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}
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#[test]
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@@ -429,7 +653,7 @@ mod tests {
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// MTP-1/2/3 measure the total movement matrix s0 -> s1
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let mtp = MtpMovementMatrix::measure(&s0, &s1);
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assert!(mtp.reversible); // constant-velocity drift is reversible
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| 432 |
-
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assert_eq!(mtp.project_reverse(&s1).serialize(), s0.serialize());
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// and forward -> s2 byte-identical (the same matrix runs both ways)
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assert_eq!(mtp.project_forward(&s1).serialize(), s0.at(2).serialize());
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@@ -439,11 +663,21 @@ mod tests {
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#[test]
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fn arrow_of_time_irreversible_step_cannot_be_retrodicted() {
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// a particle heading off the edge is CLAMPED (velocity zeroed = information lost)
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-
let s = SimState {
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| 443 |
let clamped = s.clamp_step();
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let mtp = MtpMovementMatrix::measure(&s, &clamped);
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assert!(!mtp.reversible); // the velocity changed -> the movement lost information
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-
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assert_ne!(mtp.project_reverse(&clamped).serialize(), s.serialize());
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}
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}
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}
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fn blocks(d: &[u8]) -> Vec<u128> {
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+
d.chunks(BLOCK)
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.map(|c| {
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+
let mut v = 0u128;
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for &b in c {
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v = (v << 8) | b as u128;
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+
}
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if c.len() < BLOCK {
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v <<= 8 * (BLOCK - c.len()) as u32;
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}
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v
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})
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.collect()
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}
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fn mod_inv(a: u128, m: u128) -> Option<u128> {
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fn e(a: i128, b: i128) -> (i128, i128, i128) {
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if a == 0 {
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(b, 0, 1)
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} else {
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let (g, x, y) = e(b % a, a);
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(g, y - (b / a) * x, x)
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}
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}
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if m == 0 {
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return None;
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}
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let (g, x, _) = e((a % m) as i128, m as i128);
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if g != 1 {
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return None;
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}
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Some((((x % m as i128) + m as i128) % m as i128) as u128)
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}
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/// The K shadow projections of a slice: residues of each block on each cylinder (the tomographic
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/// projections at K "angles"). Each shadow alone is lossy; enough of them reconstruct the slice.
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pub fn project_shadows(slice: &[u8]) -> Vec<Vec<u64>> {
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+
CYLINDERS
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.iter()
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.map(|&p| {
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blocks(slice)
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.iter()
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.map(|&b| (b % p as u128) as u64)
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.collect()
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})
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.collect()
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}
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/// Reconstruct the exact slice from a SUBSET of shadows (the inverse Radon / CRT). `Held` if the
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/// subset's joint modulus doesn't cover a block (under-sampled angles -> ill-posed).
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+
pub fn reconstruct(
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shadows: &[Vec<u64>],
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subset: &[usize],
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orig_len: usize,
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) -> Result<Vec<u8>, Held> {
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if subset.is_empty() {
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return Err(Held::InsufficientShadows);
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}
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let range = 1u128 << (8 * BLOCK as u32);
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let nb = shadows[subset[0]].len();
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let mut out = Vec::with_capacity(nb * BLOCK);
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let diff = (((s as i128 - r as i128) % p as i128) + p as i128) % p as i128;
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r += m * ((diff as u128 * inv) % p);
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m *= p;
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if m >= range {
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break;
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}
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}
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if m < range {
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return Err(Held::InsufficientShadows);
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}
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for i in (0..BLOCK).rev() {
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out.push(((r >> (8 * i as u32)) & 0xFF) as u8);
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}
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}
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out.truncate(orig_len);
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Ok(out)
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// ---------------------------------------------------------------- metatagged deterministic sim
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/// A metatagged particle on the bounded torus grid.
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#[derive(Debug, Clone, PartialEq, Eq)]
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+
pub struct Particle {
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pub x: u16,
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pub y: u16,
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pub vx: i16,
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pub vy: i16,
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pub tag: u32,
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}
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/// The simulated-universe STATE = a bounded grid of metatagged particles. Its serialization is the
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/// "slice"; the transition rule is constant-velocity torus drift (deterministic + REVERSIBLE, so
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/// retrodiction and extrapolation are the same operation at +/-t).
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#[derive(Debug, Clone, PartialEq, Eq)]
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+
pub struct SimState {
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pub w: u16,
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pub h: u16,
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pub particles: Vec<Particle>,
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}
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impl SimState {
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/// Canonical serialization (particles sorted by tag) -> the slice bytes.
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out
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}
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pub fn deserialize(bytes: &[u8]) -> Option<SimState> {
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if bytes.len() < 6 {
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return None;
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}
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let w = u16::from_be_bytes([bytes[0], bytes[1]]);
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let h = u16::from_be_bytes([bytes[2], bytes[3]]);
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let n = u16::from_be_bytes([bytes[4], bytes[5]]) as usize;
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if w == 0 || h == 0 {
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return None;
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}
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let mut particles = Vec::with_capacity(n);
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for i in 0..n {
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let o = 6 + i * 12;
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if o + 12 > bytes.len() {
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return None;
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}
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particles.push(Particle {
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x: u16::from_be_bytes([bytes[o], bytes[o + 1]]),
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y: u16::from_be_bytes([bytes[o + 2], bytes[o + 3]]),
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}
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/// Deterministic, reversible transition by `dt` steps (constant-velocity torus drift).
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pub fn at(&self, dt: i64) -> SimState {
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let particles = self
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.particles
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.iter()
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.map(|p| Particle {
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x: (p.x as i64 + dt * p.vx as i64).rem_euclid(self.w as i64) as u16,
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y: (p.y as i64 + dt * p.vy as i64).rem_euclid(self.h as i64) as u16,
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vx: p.vx,
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vy: p.vy,
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tag: p.tag,
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})
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.collect();
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SimState {
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w: self.w,
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h: self.h,
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particles,
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}
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}
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pub fn step_forward(&self) -> SimState {
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self.at(1)
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}
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pub fn step_backward(&self) -> SimState {
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self.at(-1)
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}
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/// An IRREVERSIBLE step (the arrow of time): a particle that would leave the grid is CLAMPED to
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/// the edge and its velocity ZEROED - the pre-collision velocity is LOST. Once this happens,
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/// reverse-propagation cannot uniquely recover the past (many pasts map to this present).
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pub fn clamp_step(&self) -> SimState {
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let particles = self
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.particles
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.iter()
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.map(|p| {
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let nx = p.x as i32 + p.vx as i32;
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let ny = p.y as i32 + p.vy as i32;
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let (x, vx) = if nx < 0 || nx >= self.w as i32 {
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(p.x, 0i16)
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} else {
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(nx as u16, p.vx)
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};
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let (y, vy) = if ny < 0 || ny >= self.h as i32 {
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(p.y, 0i16)
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} else {
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(ny as u16, p.vy)
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};
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+
Particle {
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x,
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+
y,
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+
vx,
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+
vy,
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tag: p.tag,
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+
}
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})
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.collect();
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+
SimState {
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w: self.w,
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h: self.h,
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+
particles,
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+
}
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}
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}
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// ---------------------------------------------------------------- MTP movement matrix (the "time-travel" lens)
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fn torus_delta(from: u16, to: u16, m: u16) -> i32 {
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let (d, m) = (to as i32 - from as i32, m as i32);
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+
if d > m / 2 {
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d - m
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} else if d < -m / 2 {
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d + m
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} else {
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d
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} // shortest signed torus delta
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}
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/// The total movement matrix the MTP-1/2/3 supervisors measure between two slices: per metatag,
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/// MTP1 = pixel delta (dx,dy), MTP2 = frequency/shell (speed), MTP3 = cylinder/residue (tag identity).
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for pa in &a.particles {
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match b.particles.iter().find(|pb| pb.tag == pa.tag) {
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Some(pb) => {
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+
if pb.vx != pa.vx || pb.vy != pa.vy {
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reversible = false;
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+
} // velocity lost -> irreversible
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+
moves.push((
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pa.tag,
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+
torus_delta(pa.x, pb.x, a.w),
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+
torus_delta(pa.y, pb.y, a.h),
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+
));
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}
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None => reversible = false,
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}
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MtpMovementMatrix { moves, reversible }
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}
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fn apply(&self, state: &SimState, dir: i32) -> SimState {
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+
let particles = state
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| 288 |
+
.particles
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| 289 |
+
.iter()
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+
.map(|p| {
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| 291 |
+
let (dx, dy) = self
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| 292 |
+
.moves
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+
.iter()
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| 294 |
+
.find(|(t, _, _)| *t == p.tag)
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| 295 |
+
.map(|(_, dx, dy)| (*dx, *dy))
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.unwrap_or((0, 0));
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+
Particle {
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x: (p.x as i32 + dir * dx).rem_euclid(state.w as i32) as u16,
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+
y: (p.y as i32 + dir * dy).rem_euclid(state.h as i32) as u16,
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| 300 |
+
vx: p.vx,
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+
vy: p.vy,
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| 302 |
+
tag: p.tag,
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| 303 |
+
}
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+
})
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+
.collect();
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+
SimState {
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+
w: state.w,
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+
h: state.h,
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+
particles,
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+
}
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}
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| 312 |
/// Reverse LeWorld through the lens: project the slice one tick into the PAST (retrodiction).
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+
pub fn project_reverse(&self, state: &SimState) -> SimState {
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+
self.apply(state, -1)
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+
}
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| 316 |
/// Forward LeWorld: project the slice one tick into the FUTURE.
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+
pub fn project_forward(&self, state: &SimState) -> SimState {
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+
self.apply(state, 1)
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+
}
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| 320 |
pub fn hbp(&self) -> String {
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| 321 |
format!("MTPMATRIX|moves={}|mtp1=pixel_delta|mtp2=frequency_shell|mtp3=cylinder_residue|reversible={}|lens=reverse_leworld_projection|body_in_row=0|json=0",
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self.moves.len(), self.reversible)
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| 355 |
/// The deterministic regime (steps 1-6): reconstruct t0 from shadows (multi-cylinder / Q-PRISM),
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| 356 |
/// extrapolate the KNOWN rule forward and backward, and compare each predicted slice byte-for-byte
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| 357 |
/// against generated truth. Exact in the determined regime; `Held` if shadows are insufficient.
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| 358 |
+
pub fn run_deterministic(
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| 359 |
+
truth0: &SimState,
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| 360 |
+
horizon: i64,
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| 361 |
+
subset: &[usize],
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+
) -> Result<SliceTimeReport, Held> {
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| 363 |
let slice0 = truth0.serialize();
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| 364 |
let shadows = project_shadows(&slice0);
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let recon = reconstruct(&shadows, subset, slice0.len())?;
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| 370 |
forward_exact.push((k, state0.at(k).serialize() == truth0.at(k).serialize()));
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backward_exact.push((-k, state0.at(-k).serialize() == truth0.at(-k).serialize()));
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}
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| 373 |
+
Ok(SliceTimeReport {
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+
reconstructed_ok,
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+
forward_exact,
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+
backward_exact,
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+
})
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}
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| 379 |
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| 380 |
/// The HONEST BOUNDARY (step 6): given a truth slice that GAINED entropy the rule cannot fix (an
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/// injected particle, an external input), the deterministic prediction from `state0` will NOT match.
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| 382 |
/// Returns Err(PredictionDivergedNewEntropy) - the break is DETECTED, never silently "predicted".
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| 383 |
+
pub fn verify_or_detect_entropy(
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| 384 |
+
state0: &SimState,
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| 385 |
+
observed_future: &SimState,
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| 386 |
+
dt: i64,
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| 387 |
+
) -> Result<(), Held> {
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| 388 |
if state0.at(dt).serialize() == observed_future.serialize() {
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| 389 |
Ok(()) // determined: 0-loss
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| 390 |
} else {
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| 403 |
// - no claim this IS the universe engine.
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| 404 |
|
| 405 |
#[derive(Debug, Clone, PartialEq, Eq)]
|
| 406 |
+
pub enum Verdict {
|
| 407 |
+
VerifiedClone(Vec<u8>),
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| 408 |
+
Held(HeldReason),
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| 409 |
+
}
|
| 410 |
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
|
| 411 |
+
pub enum HeldReason {
|
| 412 |
+
InsufficientShadows,
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| 413 |
+
WatcherDisagreement,
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| 414 |
+
}
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| 415 |
|
| 416 |
/// The watcher gate: reconstruct from `sufficient`; then every `cross` cylinder must agree with the
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| 417 |
/// reconstruction (catches a corrupted / hallucinated shadow). All agree -> verified classical clone.
|
| 418 |
+
pub fn watcher_gate(
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| 419 |
+
shadows: &[Vec<u64>],
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| 420 |
+
sufficient: &[usize],
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| 421 |
+
cross: &[usize],
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| 422 |
+
orig_len: usize,
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| 423 |
+
) -> Verdict {
|
| 424 |
let recon = match reconstruct(shadows, sufficient, orig_len) {
|
| 425 |
Ok(r) => r,
|
| 426 |
Err(_) => return Verdict::Held(HeldReason::InsufficientShadows),
|
| 427 |
};
|
| 428 |
for &ci in cross {
|
| 429 |
+
let recomputed: Vec<u64> = blocks(&recon)
|
| 430 |
+
.iter()
|
| 431 |
+
.map(|&b| (b % CYLINDERS[ci] as u128) as u64)
|
| 432 |
+
.collect();
|
| 433 |
+
if recomputed != shadows[ci] {
|
| 434 |
+
return Verdict::Held(HeldReason::WatcherDisagreement);
|
| 435 |
+
}
|
| 436 |
}
|
| 437 |
Verdict::VerifiedClone(recon)
|
| 438 |
}
|
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|
|
| 440 |
/// FNV-1a 64-bit fold -> an 8-byte addressing digest (NOT a crypto hash).
|
| 441 |
fn digest8(slice: &[u8]) -> [u8; 8] {
|
| 442 |
let mut h = 0xcbf29ce484222325u64;
|
| 443 |
+
for &b in slice {
|
| 444 |
+
h = (h ^ b as u64).wrapping_mul(0x100000001b3);
|
| 445 |
+
}
|
| 446 |
h.to_be_bytes()
|
| 447 |
}
|
| 448 |
+
fn hex8(b: &[u8; 8]) -> String {
|
| 449 |
+
b.iter().map(|x| format!("{:02x}", x)).collect()
|
| 450 |
+
}
|
| 451 |
|
| 452 |
/// The OMNIBIT PIXEL - one pixel carrying the representation STACK as SELECTORS + CHECKS, not raw
|
| 453 |
/// payload: position/tick/frequency, an 8-byte fold digest, the residual selector bits, the signed
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|
| 456 |
/// checks against the shared atlas. Not a magical all-information bit.
|
| 457 |
#[derive(Debug, Clone, PartialEq, Eq)]
|
| 458 |
pub struct OmnibitPixel {
|
| 459 |
+
pub x: u16,
|
| 460 |
+
pub y: u16,
|
| 461 |
+
pub tick: u32,
|
| 462 |
+
pub freq: u16,
|
| 463 |
pub digest8: [u8; 8],
|
| 464 |
pub residual_bits: u8,
|
| 465 |
pub capacity_margin_bits: i32,
|
| 466 |
pub watcher_bound: u8,
|
| 467 |
}
|
| 468 |
impl OmnibitPixel {
|
| 469 |
+
pub fn of(
|
| 470 |
+
slice: &[u8],
|
| 471 |
+
x: u16,
|
| 472 |
+
y: u16,
|
| 473 |
+
tick: u32,
|
| 474 |
+
freq: u16,
|
| 475 |
+
n_cylinders: usize,
|
| 476 |
+
watcher_bound: u8,
|
| 477 |
+
) -> Self {
|
| 478 |
let roof = (n_cylinders.min(CYLINDERS.len()) as f64) * 25.0; // ~log2(2^25) per cylinder
|
| 479 |
let block_bits = (8 * BLOCK) as f64;
|
| 480 |
OmnibitPixel {
|
| 481 |
+
x,
|
| 482 |
+
y,
|
| 483 |
+
tick,
|
| 484 |
+
freq,
|
| 485 |
+
digest8: digest8(slice),
|
| 486 |
residual_bits: (block_bits - roof).max(0.0).ceil() as u8,
|
| 487 |
capacity_margin_bits: (roof - block_bits) as i32,
|
| 488 |
watcher_bound,
|
|
|
|
| 501 |
|
| 502 |
fn sample_state() -> SimState {
|
| 503 |
SimState {
|
| 504 |
+
w: 64,
|
| 505 |
+
h: 48,
|
| 506 |
particles: vec![
|
| 507 |
+
Particle {
|
| 508 |
+
x: 3,
|
| 509 |
+
y: 5,
|
| 510 |
+
vx: 2,
|
| 511 |
+
vy: -1,
|
| 512 |
+
tag: 1,
|
| 513 |
+
},
|
| 514 |
+
Particle {
|
| 515 |
+
x: 60,
|
| 516 |
+
y: 1,
|
| 517 |
+
vx: -3,
|
| 518 |
+
vy: 4,
|
| 519 |
+
tag: 2,
|
| 520 |
+
},
|
| 521 |
+
Particle {
|
| 522 |
+
x: 31,
|
| 523 |
+
y: 24,
|
| 524 |
+
vx: 1,
|
| 525 |
+
vy: 1,
|
| 526 |
+
tag: 3,
|
| 527 |
+
},
|
| 528 |
+
Particle {
|
| 529 |
+
x: 0,
|
| 530 |
+
y: 47,
|
| 531 |
+
vx: 5,
|
| 532 |
+
vy: -2,
|
| 533 |
+
tag: 4,
|
| 534 |
+
},
|
| 535 |
],
|
| 536 |
}
|
| 537 |
}
|
|
|
|
| 540 |
fn serialize_roundtrips() {
|
| 541 |
let s = sample_state();
|
| 542 |
assert_eq!(SimState::deserialize(&s.serialize()).unwrap(), {
|
| 543 |
+
let mut c = s.clone();
|
| 544 |
+
c.particles.sort_by_key(|p| p.tag);
|
| 545 |
+
c
|
| 546 |
});
|
| 547 |
}
|
| 548 |
|
|
|
|
| 550 |
fn rule_is_reversible() {
|
| 551 |
let s = sample_state();
|
| 552 |
for k in 1..=20 {
|
| 553 |
+
assert_eq!(
|
| 554 |
+
s.at(k).at(-k).serialize(),
|
| 555 |
+
s.serialize(),
|
| 556 |
+
"at(+{k}).at(-{k}) must be identity"
|
| 557 |
+
);
|
| 558 |
}
|
| 559 |
}
|
| 560 |
|
|
|
|
| 564 |
// enough shadows (all 4 cylinders) -> full state reconstructed -> every slice exact both ways
|
| 565 |
let report = run_deterministic(&s, 25, &[0, 1, 2, 3]).unwrap();
|
| 566 |
assert!(report.reconstructed_ok);
|
| 567 |
+
assert!(
|
| 568 |
+
report.all_exact(),
|
| 569 |
+
"determined regime: past AND future slices are 0-loss"
|
| 570 |
+
);
|
| 571 |
assert_eq!(report.forward_exact.len(), 25);
|
| 572 |
assert_eq!(report.backward_exact.len(), 25);
|
| 573 |
}
|
|
|
|
| 576 |
fn two_shadows_already_suffice_one_holds() {
|
| 577 |
let s = sample_state();
|
| 578 |
assert!(run_deterministic(&s, 5, &[0, 1]).unwrap().all_exact()); // 2 cylinders cover a 48-bit block
|
| 579 |
+
assert!(matches!(
|
| 580 |
+
run_deterministic(&s, 5, &[0]),
|
| 581 |
+
Err(Held::InsufficientShadows)
|
| 582 |
+
)); // 1 -> Shannon Held
|
| 583 |
}
|
| 584 |
|
| 585 |
#[test]
|
|
|
|
| 589 |
assert!(verify_or_detect_entropy(&s, &s.at(7), 7).is_ok());
|
| 590 |
// but a future that GAINED entropy (an injected particle) is DETECTED, never manufactured:
|
| 591 |
let mut injected = s.at(7);
|
| 592 |
+
injected.particles.push(Particle {
|
| 593 |
+
x: 9,
|
| 594 |
+
y: 9,
|
| 595 |
+
vx: 0,
|
| 596 |
+
vy: 0,
|
| 597 |
+
tag: 9999,
|
| 598 |
+
});
|
| 599 |
+
assert_eq!(
|
| 600 |
+
verify_or_detect_entropy(&s, &injected, 7),
|
| 601 |
+
Err(Held::PredictionDivergedNewEntropy)
|
| 602 |
+
);
|
| 603 |
}
|
| 604 |
|
| 605 |
#[test]
|
|
|
|
| 615 |
let slice = b"the yin-yang watcher: black-absorb, white-emit, round-trip or Held";
|
| 616 |
let shadows = project_shadows(slice);
|
| 617 |
// clean: reconstruct from [0,1], cross-check [2,3] -> verified classical clone
|
| 618 |
+
assert_eq!(
|
| 619 |
+
watcher_gate(&shadows, &[0, 1], &[2, 3], slice.len()),
|
| 620 |
+
Verdict::VerifiedClone(slice.to_vec())
|
| 621 |
+
);
|
| 622 |
// tamper a sufficient shadow -> the cross cylinders catch the hallucination -> Held
|
| 623 |
let mut tampered = shadows.clone();
|
| 624 |
tampered[0][0] = tampered[0][0].wrapping_add(1);
|
| 625 |
+
assert_eq!(
|
| 626 |
+
watcher_gate(&tampered, &[0, 1], &[2, 3], slice.len()),
|
| 627 |
+
Verdict::Held(HeldReason::WatcherDisagreement)
|
| 628 |
+
);
|
| 629 |
// too few -> Held (Shannon)
|
| 630 |
+
assert_eq!(
|
| 631 |
+
watcher_gate(&shadows, &[0], &[], slice.len()),
|
| 632 |
+
Verdict::Held(HeldReason::InsufficientShadows)
|
| 633 |
+
);
|
| 634 |
}
|
| 635 |
|
| 636 |
#[test]
|
|
|
|
| 641 |
assert!(px2.capacity_margin_bits >= 0); // over-determination margin, never negative storage
|
| 642 |
let px1 = OmnibitPixel::of(slice, 3, 5, 7, 440, 1, 0);
|
| 643 |
assert!(px1.residual_bits > 0); // 1 cylinder under-covers -> residual selector remains
|
| 644 |
+
assert!(
|
| 645 |
+
px2.to_hbp().contains("payload=selector-not-raw") && px2.to_hbp().ends_with("json=0")
|
| 646 |
+
);
|
| 647 |
}
|
| 648 |
|
| 649 |
#[test]
|
|
|
|
| 653 |
// MTP-1/2/3 measure the total movement matrix s0 -> s1
|
| 654 |
let mtp = MtpMovementMatrix::measure(&s0, &s1);
|
| 655 |
assert!(mtp.reversible); // constant-velocity drift is reversible
|
| 656 |
+
// "time travel": from s1, the lens projects the reverse slice -> s0 byte-identical (retrodiction)
|
| 657 |
assert_eq!(mtp.project_reverse(&s1).serialize(), s0.serialize());
|
| 658 |
// and forward -> s2 byte-identical (the same matrix runs both ways)
|
| 659 |
assert_eq!(mtp.project_forward(&s1).serialize(), s0.at(2).serialize());
|
|
|
|
| 663 |
#[test]
|
| 664 |
fn arrow_of_time_irreversible_step_cannot_be_retrodicted() {
|
| 665 |
// a particle heading off the edge is CLAMPED (velocity zeroed = information lost)
|
| 666 |
+
let s = SimState {
|
| 667 |
+
w: 10,
|
| 668 |
+
h: 10,
|
| 669 |
+
particles: vec![Particle {
|
| 670 |
+
x: 9,
|
| 671 |
+
y: 5,
|
| 672 |
+
vx: 3,
|
| 673 |
+
vy: 0,
|
| 674 |
+
tag: 1,
|
| 675 |
+
}],
|
| 676 |
+
};
|
| 677 |
let clamped = s.clamp_step();
|
| 678 |
let mtp = MtpMovementMatrix::measure(&s, &clamped);
|
| 679 |
assert!(!mtp.reversible); // the velocity changed -> the movement lost information
|
| 680 |
+
// reverse-propagating the clamped present does NOT recover the true past -> the arrow of time bites
|
| 681 |
assert_ne!(mtp.project_reverse(&clamped).serialize(), s.serialize());
|
| 682 |
}
|
| 683 |
}
|